Induction-type watt hour meters typically employ a pulse initiator which generates pulses in proportion to the rate of rotation of a meter disk. These generated pulses are transmitted to electronic registers for deriving current, voltage, power and/or time of use energy consumption.
Various types of solid state polyphase electronic meters are also in common use today. These meters, which monitor electrical energy consumption and record or report such consumption in kilowatt hours, power factor, KVA, and/or reactive volt amperes, typically employ solid state components, and may utilize analog-to-digital converters to provide digital data rather than pulse data from which various demand/consumption indicators can be extracted.
It is also well known to provide solid state electronic meters which may be configurable for installation in any one of a variety of single or multi-phase electricity distribution systems. One example of a solid state electronic watt hour meter is disclosed in U.S. Pat. No. 5,059,896, issued to Germer et al.
An example of a solid state electricity demand recorder which may be used in conjunction with a conventional watt hour meter is disclosed in U.S. Pat. No. 4,697,182, issued to Swanson.
Various ancillary equipment and diagnostic techniques are utilized by service personnel during installation of these meters in attempting to confirm that the installation has been wired correctly. However, many installation checks, such as polarity and cross-phase checks, are derived on site by field personnel and are therefore dependent upon the knowledge and competence of those personnel.
While various diagnostic equipment is available for use by field personnel during installation and periodic maintenance, a need exists for an integral apparatus which automatically and periodically performs a standard series of system and installation diagnostics without interrupting the operation of the meter. In addition, there is a need for periodic self-checks of the meter to determine and record the occurrence of selected pre-defined fatal and non-fatal errors in the meter's operation.